Aging Of Organisms

Biological aging as the time-depending general decline of biological systems associated with a progressively increasing mortality risk is a general phenomenom of great significance. The underlying processes are very complex and depending on genetic and environment factors. These factors encode or affect a network of interconnected cellular pathways. In no system this network has been deciphered in greater detail. However, the strategy of studying various biological systems has let to the identification of pathways and specific modules and makes it obvious that aging is the result of different overlapping mechanisms and pathways. Some of these appear to be conserved ("public") among species, others are specific or "private" and only of significance in one or a few organisms. This volume in the series on "Biology of aging and its modulation" specifically focuses on organismic aging. The book covers research on organisms from lower to higher complexity representing examples from very diverse taxa like photosynthetic plants, fungi, sponges, nematodes, flies, birds and mammals. Such a broad treatise of this complex topic provides a comprehensive "flavor" about the current issues dealt with in this rapidly growing scientific discipline.

Time, Cells, and Aging, 2nd Edition presents the mechanics of cell function and the relevant implications of the molecular-genetic view to the aging phenomena. This book explores the biology of the aging process. Comprised of 11 chapters, this edition starts with an overview of the causes and mechanisms underlying the gradual deterioration of structure and function characteristics of aging. This text then examines the two aspects of the behavior of man, including the reasoned conscious behavior and the greater dependence on reaction patterns predicted on the successful responses of the past. Other chapters explore the relationship between aging and mortality rate in animals, which is a result of an organism's deceasing ability to function optimally in carrying out his vital functions. The final chapter deals with the implementation of a research plan relevant to understanding the primary mechanisms of the aging process. This book is a valuable resource for gerontologists, biologists, and molecular biologists.

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The survival of the human species has improved significantly in modern times. During the last century, the mean survival of human populations in developed countries has increased more than during the preceding 5000 years. This improvement in survival was accompanied by an increase in the number of active years. In other words, the increase in mean life span was accompanied by an increase in health span. This is now accentuated by progress in medicine reducing the impact of physiologic events such as menopause and of patho logical processes such as atherosclerosis. Up to now,research on aging, whether theoretical or experimental, has not contributed to improvement in human survival. Actually, there is a striking contrast between these significant modifications in survival and the present knowledge of the mechanisms of human aging. Revealed by this state of affairs are the profound disagreements between gerontologists in regard to the way oflooking at the aging process. The definition of aging itself is difficult to begin with because of the variability of how it occurs in different organisms.

Handbook of the Biology of Aging, Eighth Edition, provides readers with an update on the rapid progress in the research of aging. It is a comprehensive synthesis and review of the latest and most important advances and themes in modern biogerontology, and focuses on the trend of ‘big data’ approaches in the biological sciences, presenting new strategies to analyze, interpret, and understand the enormous amounts of information being generated through DNA sequencing, transcriptomic, proteomic, and the metabolomics methodologies applied to aging related problems. The book includes discussions on longevity pathways and interventions that modulate aging, innovative new tools that facilitate systems-level approaches to aging research, the mTOR pathway and its importance in age-related phenotypes, new strategies to pharmacologically modulate the mTOR pathway to delay aging, the importance of sirtuins and the hypoxic response in aging, and how various pathways interact within the context of aging as a complex genetic trait, amongst others. Covers the key areas in biological gerontology research in one volume, with an 80% update from the previous edition Edited by Matt Kaeberlein and George Martin, highly respected voices and researchers within the biology of aging discipline Assists basic researchers in keeping abreast of research and clinical findings outside their subdiscipline Presents information that will help medical, behavioral, and social gerontologists in understanding what basic scientists and clinicians are discovering New chapters on genetics, evolutionary biology, bone aging, and epigenetic control Provides a close examination of the diverse research being conducted today in the study of the biology of aging, detailing recent breakthroughs and potential new directions

Recent studies have indicated that epigenetic processes may play a major role in both cellular and organismal aging. These epigenetic processes include not only DNA methylation and histone modifications, but also extend to many other epigenetic mediators such as the polycomb group proteins, chromosomal position effects, and noncoding RNA. The topics of this book range from fundamental changes in DNA methylation in aging to the most recent research on intervention into epigenetic modifications to modulate the aging process. The major topics of epigenetics and aging covered in this book are: 1) DNA methylation and histone modifications in aging; 2) Other epigenetic processes and aging; 3) Impact of epigenetics on aging; 4) Epigenetics of age-related diseases; 5) Epigenetic interventions and aging: and 6) Future directions in epigenetic aging research. The most studied of epigenetic processes, DNA methylation, has been associated with cellular aging and aging of organisms for many years. It is now apparent that both global and gene-specific alterations occur not only in DNA methylation during aging, but also in several histone alterations. Many epigenetic alterations can have an impact on aging processes such as stem cell aging, control of telomerase, modifications of telomeres, and epigenetic drift can impact the aging process as evident in the recent studies of aging monozygotic twins. Numerous age-related diseases are affected by epigenetic mechanisms. For example, recent studies have shown that DNA methylation is altered in Alzheimer’s disease and autoimmunity. Other prevalent diseases that have been associated with age-related epigenetic changes include cancer and diabetes. Paternal age and epigenetic changes appear to have an effect on schizophrenia and epigenetic silencing has been associated with several of the progeroid syndromes of premature aging. Moreover, the impact of dietary or drug intervention into epigenetic processes as they affect normal aging or age-related diseases is becoming increasingly feasible.

Stem Cells and Aging covers what is known about the effect of time and age on the basic units of life, which are the corresponding tissue-specific or adult stem cells. Even though the concept of stem cells was introduced nearly a century ago by Alexander Maximow, modern stem-cell research began in 1963 when James Till, Ernest McCullough and Lou Siminovitch established assays to detect hematopoietic stem cells. In fact, given the importance of the aging-associated diseases, scientists have developed a keen interest in understanding the aging process as they attempt to define the role of dysfunctional stem cells in the aging process. With an aging population worldwide, understanding these age-related stem cell changes at a basic biology level and at the level of their influences for regenerative medicine is of interest and importance. There is increasing evidence that the aging process can have much adverse effects on stem cells. In the modern era, one of the emerging fields in treating human diseases is stem cell research, as stem cells have the remarkable potential to treat a wide range of diseases. Nevertheless, understanding the molecular mechanism involved in aging and deterioration of stem cell function is crucial in developing effective new therapies for aging. Serves as an ideal reference to guide investigators toward valuable answers to the problems of our aging population Addresses the effect of time and age on human stem cells Includes chapters from contributors exploring the biology of stem cell aging around the globe